What Are the Test Characteristics of HIV Antibody Test Strategies?
The use of repeatedly reactive enzyme immunoassay followed by confirmatory Western blot or immunofluorescent assay remains the standard method for diagnosing HIV-1 infection.44,45 A large study of HIV testing in 752 U.S. laboratories reported a sensitivity of 99.7% and specificity of 98.5% for enzyme immunoassay,45 and studies in U.S. blood donors reported specificities of 99.8% and greater than 99.99%.46,47 With confirmatory Western blot, the chance of a false-positive identification in a low-prevalence setting is about 1 in 250 000 (95% CI, 1 in 173,000 to 1 in 379,000).48 Three rapid (results available in 10 to 30 minutes) HIV tests are in use in the United States; 2 (Uni-Gold Recombigen, Trinity Biotech Plc., Bray, Ireland, and OraQuick Advance, OraSure Technologies, Bethlehem, Pennsylvania) for true point-of-care testing,49 and 1 (Reveal G2, MedMira Laboratories, Inc., Halifax, Nova Scotia, Canada) performed in a laboratory. Three good-quality and 10 fair-quality studies evaluated
